/*
 * WPA Supplicant / SSL  LS interface functions for openssl
 * Copyright (c) 2004-2008, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"

#ifndef CONFIG_SMARTCARD
#ifndef OPENSSL_NO_ENGINE
#define OPENSSL_NO_ENGINE
#endif
#endif

#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/pkcs12.h>
#include <openssl/x509v3.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif /* OPENSSL_NO_ENGINE */

#include "common.h"
#include "tls.h"

#if OPENSSL_VERSION_NUMBER >= 0x0090800fL
#define OPENSSL_d2i_TYPE const unsigned char **
#else
#define OPENSSL_d2i_TYPE unsigned char **
#endif

#ifdef SSL_F_SSL_SET_SESSION_TICKET_EXT
#ifdef SSL_OP_NO_TICKET
/*
 * Session ticket override patch was merged into OpenSSL 0.9.9 tree on
 * 2008-11-15. This version uses a bit different API compared to the old patch.
 */
#define CONFIG_OPENSSL_TICKET_OVERRIDE
#endif
#endif

static int tls_openssl_ref_count = 0;

struct tls_connection {
        SSL *ssl;
        BIO *ssl_in, *ssl_out;
#ifndef OPENSSL_NO_ENGINE
        ENGINE *engine;        /* functional reference to the engine */
        EVP_PKEY *private_key; /* the private key if using engine */
#endif /* OPENSSL_NO_ENGINE */
        char *subject_match, *altsubject_match;
        int read_alerts, write_alerts, failed;

        tls_session_ticket_cb session_ticket_cb;
        void *session_ticket_cb_ctx;

        /* SessionTicket received from OpenSSL hello_extension_cb (server) */
        u8 *session_ticket;
        size_t session_ticket_len;
};


#ifdef CONFIG_NO_STDOUT_DEBUG

static void _tls_show_errors(void)
{
        unsigned long err;

        while ((err = ERR_get_error())) {
                /* Just ignore the errors, since stdout is disabled */
        }
}
#define tls_show_errors(l, f, t) _tls_show_errors()

#else /* CONFIG_NO_STDOUT_DEBUG */

static void tls_show_errors(int level, const char *func, const char *txt)
{
        unsigned long err;

        wpa_printf(level, "OpenSSL: %s - %s %s",
                   func, txt, ERR_error_string(ERR_get_error(), NULL));

        while ((err = ERR_get_error())) {
                wpa_printf(MSG_INFO, "OpenSSL: pending error: %s",
                           ERR_error_string(err, NULL));
        }
}

#endif /* CONFIG_NO_STDOUT_DEBUG */


#ifdef CONFIG_NATIVE_WINDOWS

/* Windows CryptoAPI and access to certificate stores */
#include <wincrypt.h>

#ifdef __MINGW32_VERSION
/*
 * MinGW does not yet include all the needed definitions for CryptoAPI, so
 * define here whatever extra is needed.
 */
#define CERT_SYSTEM_STORE_CURRENT_USER (1 << 16)
#define CERT_STORE_READONLY_FLAG 0x00008000
#define CERT_STORE_OPEN_EXISTING_FLAG 0x00004000

#endif /* __MINGW32_VERSION */


struct cryptoapi_rsa_data {
        const CERT_CONTEXT *cert;
        HCRYPTPROV crypt_prov;
        DWORD key_spec;
        BOOL free_crypt_prov;
};


static void cryptoapi_error(const char *msg)
{
        wpa_printf(MSG_INFO, "CryptoAPI: %s; err=%u",
                   msg, (unsigned int) GetLastError());
}


static int cryptoapi_rsa_pub_enc(int flen, const unsigned char *from,
                                 unsigned char *to, RSA *rsa, int padding)
{
        wpa_printf(MSG_DEBUG, "%s - not implemented", __func__);
        return 0;
}


static int cryptoapi_rsa_pub_dec(int flen, const unsigned char *from,
                                 unsigned char *to, RSA *rsa, int padding)
{
        wpa_printf(MSG_DEBUG, "%s - not implemented", __func__);
        return 0;
}


static int cryptoapi_rsa_priv_enc(int flen, const unsigned char *from,
                                  unsigned char *to, RSA *rsa, int padding)
{
        struct cryptoapi_rsa_data *priv =
                (struct cryptoapi_rsa_data *) rsa->meth->app_data;
        HCRYPTHASH hash;
        DWORD hash_size, len, i;
        unsigned char *buf = NULL;
        int ret = 0;

        if (priv == NULL) {
                RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,
                       ERR_R_PASSED_NULL_PARAMETER);
                return 0;
        }

        if (padding != RSA_PKCS1_PADDING) {
                RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,
                       RSA_R_UNKNOWN_PADDING_TYPE);
                return 0;
        }

        if (flen != 16 /* MD5 */ + 20 /* SHA-1 */) {
                wpa_printf(MSG_INFO, "%s - only MD5-SHA1 hash supported",
                           __func__);
                RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,
                       RSA_R_INVALID_MESSAGE_LENGTH);
                return 0;
        }

        if (!CryptCreateHash(priv->crypt_prov, CALG_SSL3_SHAMD5, 0, 0, &hash))
        {
                cryptoapi_error("CryptCreateHash failed");
                return 0;
        }

        len = sizeof(hash_size);
        if (!CryptGetHashParam(hash, HP_HASHSIZE, (BYTE *) &hash_size, &len,
                               0)) {
                cryptoapi_error("CryptGetHashParam failed");
                goto err;
        }

        if ((int) hash_size != flen) {
                wpa_printf(MSG_INFO, "CryptoAPI: Invalid hash size (%u != %d)",
                           (unsigned) hash_size, flen);
                RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT,
                       RSA_R_INVALID_MESSAGE_LENGTH);
                goto err;
        }
        if (!CryptSetHashParam(hash, HP_HASHVAL, (BYTE * ) from, 0)) {
                cryptoapi_error("CryptSetHashParam failed");
                goto err;
        }

        len = RSA_size(rsa);
        buf = os_malloc(len);
        if (buf == NULL) {
                RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_MALLOC_FAILURE);
                goto err;
        }

        if (!CryptSignHash(hash, priv->key_spec, NULL, 0, buf, &len)) {
                cryptoapi_error("CryptSignHash failed");
                goto err;
        }

        for (i = 0; i < len; i++)
                to[i] = buf[len - i - 1];
        ret = len;

err:
        os_free(buf);
        CryptDestroyHash(hash);

        return ret;
}


static int cryptoapi_rsa_priv_dec(int flen, const unsigned char *from,
                                  unsigned char *to, RSA *rsa, int padding)
{
        wpa_printf(MSG_DEBUG, "%s - not implemented", __func__);
        return 0;
}


static void cryptoapi_free_data(struct cryptoapi_rsa_data *priv)
{
        if (priv == NULL)
                return;
        if (priv->crypt_prov && priv->free_crypt_prov)
                CryptReleaseContext(priv->crypt_prov, 0);
        if (priv->cert)
                CertFreeCertificateContext(priv->cert);
        os_free(priv);
}


static int cryptoapi_finish(RSA *rsa)
{
        cryptoapi_free_data((struct cryptoapi_rsa_data *) rsa->meth->app_data);
        os_free((void *) rsa->meth);
        rsa->meth = NULL;
        return 1;
}


static const CERT_CONTEXT * cryptoapi_find_cert(const char *name, DWORD store)
{
        HCERTSTORE cs;
        const CERT_CONTEXT *ret = NULL;

        cs = CertOpenStore((LPCSTR) CERT_STORE_PROV_SYSTEM, 0, 0,
                           store | CERT_STORE_OPEN_EXISTING_FLAG |
                           CERT_STORE_READONLY_FLAG, L"MY");
        if (cs == NULL) {
                cryptoapi_error("Failed to open 'My system store'");
                return NULL;
        }

        if (strncmp(name, "cert://", 7) == 0) {
                unsigned short wbuf[255];
                MultiByteToWideChar(CP_ACP, 0, name + 7, -1, wbuf, 255);
                ret = CertFindCertificateInStore(cs, X509_ASN_ENCODING |
                                                 PKCS_7_ASN_ENCODING,
                                                 0, CERT_FIND_SUBJECT_STR,
                                                 wbuf, NULL);
        } else if (strncmp(name, "hash://", 7) == 0) {
                CRYPT_HASH_BLOB blob;
                int len;
                const char *hash = name + 7;
                unsigned char *buf;

                len = os_strlen(hash) / 2;
                buf = os_malloc(len);
                if (buf && hexstr2bin(hash, buf, len) == 0) {
                        blob.cbData = len;
                        blob.pbData = buf;
                        ret = CertFindCertificateInStore(cs,
                                                         X509_ASN_ENCODING |
                                                         PKCS_7_ASN_ENCODING,
                                                         0, CERT_FIND_HASH,
                                                         &blob, NULL);
                }
                os_free(buf);
        }

        CertCloseStore(cs, 0);

        return ret;
}


static int tls_cryptoapi_cert(SSL *ssl, const char *name)
{
        X509 *cert = NULL;
        RSA *rsa = NULL, *pub_rsa;
        struct cryptoapi_rsa_data *priv;
        RSA_METHOD *rsa_meth;

        if (name == NULL ||
            (strncmp(name, "cert://", 7) != 0 &&
             strncmp(name, "hash://", 7) != 0))
                return -1;

        priv = os_zalloc(sizeof(*priv));
        rsa_meth = os_zalloc(sizeof(*rsa_meth));
        if (priv == NULL || rsa_meth == NULL) {
                wpa_printf(MSG_WARNING, "CryptoAPI: Failed to allocate memory "
                           "for CryptoAPI RSA method");
                os_free(priv);
                os_free(rsa_meth);
                return -1;
        }

        priv->cert = cryptoapi_find_cert(name, CERT_SYSTEM_STORE_CURRENT_USER);
        if (priv->cert == NULL) {
                priv->cert = cryptoapi_find_cert(
                        name, CERT_SYSTEM_STORE_LOCAL_MACHINE);
        }
        if (priv->cert == NULL) {
                wpa_printf(MSG_INFO, "CryptoAPI: Could not find certificate "
                           "'%s'", name);
                goto err;
        }

        cert = d2i_X509(NULL, (OPENSSL_d2i_TYPE) &priv->cert->pbCertEncoded,
                        priv->cert->cbCertEncoded);
        if (cert == NULL) {
                wpa_printf(MSG_INFO, "CryptoAPI: Could not process X509 DER "
                           "encoding");
                goto err;
        }

        if (!CryptAcquireCertificatePrivateKey(priv->cert,
                                               CRYPT_ACQUIRE_COMPARE_KEY_FLAG,
                                               NULL, &priv->crypt_prov,
                                               &priv->key_spec,
                                               &priv->free_crypt_prov)) {
                cryptoapi_error("Failed to acquire a private key for the "
                                "certificate");
                goto err;
        }

        rsa_meth->name = "Microsoft CryptoAPI RSA Method";
        rsa_meth->rsa_pub_enc = cryptoapi_rsa_pub_enc;
        rsa_meth->rsa_pub_dec = cryptoapi_rsa_pub_dec;
        rsa_meth->rsa_priv_enc = cryptoapi_rsa_priv_enc;
        rsa_meth->rsa_priv_dec = cryptoapi_rsa_priv_dec;
        rsa_meth->finish = cryptoapi_finish;
        rsa_meth->flags = RSA_METHOD_FLAG_NO_CHECK;
        rsa_meth->app_data = (char *) priv;

        rsa = RSA_new();
        if (rsa == NULL) {
                SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_FILE,
                       ERR_R_MALLOC_FAILURE);
                goto err;
        }

        if (!SSL_use_certificate(ssl, cert)) {
                RSA_free(rsa);
                rsa = NULL;
                goto err;
        }
        pub_rsa = cert->cert_info->key->pkey->pkey.rsa;
        X509_free(cert);
        cert = NULL;

        rsa->n = BN_dup(pub_rsa->n);
        rsa->e = BN_dup(pub_rsa->e);
        if (!RSA_set_method(rsa, rsa_meth))
                goto err;

        if (!SSL_use_RSAPrivateKey(ssl, rsa))
                goto err;
        RSA_free(rsa);

        return 0;

err:
        if (cert)
                X509_free(cert);
        if (rsa)
                RSA_free(rsa);
        else {
                os_free(rsa_meth);
                cryptoapi_free_data(priv);
        }
        return -1;
}


static int tls_cryptoapi_ca_cert(SSL_CTX *ssl_ctx, SSL *ssl, const char *name)
{
        HCERTSTORE cs;
        PCCERT_CONTEXT ctx = NULL;
        X509 *cert;
        char buf[128];
        const char *store;
#ifdef UNICODE
        WCHAR *wstore;
#endif /* UNICODE */

        if (name == NULL || strncmp(name, "cert_store://", 13) != 0)
                return -1;

        store = name + 13;
#ifdef UNICODE
        wstore = os_malloc((os_strlen(store) + 1) * sizeof(WCHAR));
        if (wstore == NULL)
                return -1;
        wsprintf(wstore, L"%S", store);
        cs = CertOpenSystemStore(0, wstore);
        os_free(wstore);
#else /* UNICODE */
        cs = CertOpenSystemStore(0, store);
#endif /* UNICODE */
        if (cs == NULL) {
                wpa_printf(MSG_DEBUG, "%s: failed to open system cert store "
                           "'%s': error=%d", __func__, store,
                           (int) GetLastError());
                return -1;
        }

        while ((ctx = CertEnumCertificatesInStore(cs, ctx))) {
                cert = d2i_X509(NULL, (OPENSSL_d2i_TYPE) &ctx->pbCertEncoded,
                                ctx->cbCertEncoded);
                if (cert == NULL) {
                        wpa_printf(MSG_INFO, "CryptoAPI: Could not process "
                                   "X509 DER encoding for CA cert");
                        continue;
                }

                X509_NAME_oneline(X509_get_subject_name(cert), buf,
                                  sizeof(buf));
                wpa_printf(MSG_DEBUG, "OpenSSL: Loaded CA certificate for "
                           "system certificate store: subject='%s'", buf);

                if (!X509_STORE_add_cert(ssl_ctx->cert_store, cert)) {
                        tls_show_errors(MSG_WARNING, __func__,
                                        "Failed to add ca_cert to OpenSSL "
                                        "certificate store");
                }

                X509_free(cert);
        }

        if (!CertCloseStore(cs, 0)) {
                wpa_printf(MSG_DEBUG, "%s: failed to close system cert store "
                           "'%s': error=%d", __func__, name + 13,
                           (int) GetLastError());
        }

        return 0;
}


#else /* CONFIG_NATIVE_WINDOWS */

static int tls_cryptoapi_cert(SSL *ssl, const char *name)
{
        return -1;
}

#endif /* CONFIG_NATIVE_WINDOWS */


static void ssl_info_cb(const SSL *ssl, int where, int ret)
{
        const char *str;
        int w;

        wpa_printf(MSG_DEBUG, "SSL: (where=0x%x ret=0x%x)", where, ret);
        w = where & ~SSL_ST_MASK;
        if (w & SSL_ST_CONNECT)
                str = "SSL_connect";
        else if (w & SSL_ST_ACCEPT)
                str = "SSL_accept";
        else
                str = "undefined";

        if (where & SSL_CB_LOOP) {
                wpa_printf(MSG_DEBUG, "SSL: %s:%s",
                           str, SSL_state_string_long(ssl));
        } else if (where & SSL_CB_ALERT) {
                wpa_printf(MSG_INFO, "SSL: SSL3 alert: %s:%s:%s",
                           where & SSL_CB_READ ?
                           "read (remote end reported an error)" :
                           "write (local SSL3 detected an error)",
                           SSL_alert_type_string_long(ret),
                           SSL_alert_desc_string_long(ret));
                if ((ret >> 8) == SSL3_AL_FATAL) {
                        struct tls_connection *conn =
                                SSL_get_app_data((SSL *) ssl);
                        if (where & SSL_CB_READ)
                                conn->read_alerts++;
                        else
                                conn->write_alerts++;
                }
        } else if (where & SSL_CB_EXIT && ret <= 0) {
                wpa_printf(MSG_DEBUG, "SSL: %s:%s in %s",
                           str, ret == 0 ? "failed" : "error",
                           SSL_state_string_long(ssl));
        }
}


#ifndef OPENSSL_NO_ENGINE
/**
 * tls_engine_load_dynamic_generic - load any openssl engine
 * @pre: an array of commands and values that load an engine initialized
 *       in the engine specific function
 * @post: an array of commands and values that initialize an already loaded
 *        engine (or %NULL if not required)
 * @id: the engine id of the engine to load (only required if post is not %NULL
 *
 * This function is a generic function that loads any openssl engine.
 *
 * Returns: 0 on success, -1 on failure
 */
static int tls_engine_load_dynamic_generic(const char *pre[],
                                           const char *post[], const char *id)
{
        ENGINE *engine;
        const char *dynamic_id = "dynamic";

        engine = ENGINE_by_id(id);
        if (engine) {
                ENGINE_free(engine);
                wpa_printf(MSG_DEBUG, "ENGINE: engine '%s' is already "
                           "available", id);
                return 0;
        }
        ERR_clear_error();

        engine = ENGINE_by_id(dynamic_id);
        if (engine == NULL) {
                wpa_printf(MSG_INFO, "ENGINE: Can't find engine %s [%s]",
                           dynamic_id,
                           ERR_error_string(ERR_get_error(), NULL));
                return -1;
        }

        /* Perform the pre commands. This will load the engine. */
        while (pre && pre[0]) {
                wpa_printf(MSG_DEBUG, "ENGINE: '%s' '%s'", pre[0], pre[1]);
                if (ENGINE_ctrl_cmd_string(engine, pre[0], pre[1], 0) == 0) {
                        wpa_printf(MSG_INFO, "ENGINE: ctrl cmd_string failed: "
                                   "%s %s [%s]", pre[0], pre[1],
                                   ERR_error_string(ERR_get_error(), NULL));
                        ENGINE_free(engine);
                        return -1;
                }
                pre += 2;
        }

        /*
         * Free the reference to the "dynamic" engine. The loaded engine can
         * now be looked up using ENGINE_by_id().
         */
        ENGINE_free(engine);

        engine = ENGINE_by_id(id);
        if (engine == NULL) {
                wpa_printf(MSG_INFO, "ENGINE: Can't find engine %s [%s]",
                           id, ERR_error_string(ERR_get_error(), NULL));
                return -1;
        }

        while (post && post[0]) {
                wpa_printf(MSG_DEBUG, "ENGINE: '%s' '%s'", post[0], post[1]);
                if (ENGINE_ctrl_cmd_string(engine, post[0], post[1], 0) == 0) {
                        wpa_printf(MSG_DEBUG, "ENGINE: ctrl cmd_string failed:"
                                " %s %s [%s]", post[0], post[1],
                                   ERR_error_string(ERR_get_error(), NULL));
                        ENGINE_remove(engine);
                        ENGINE_free(engine);
                        return -1;
                }
                post += 2;
        }
        ENGINE_free(engine);

        return 0;
}


/**
 * tls_engine_load_dynamic_pkcs11 - load the pkcs11 engine provided by opensc
 * @pkcs11_so_path: pksc11_so_path from the configuration
 * @pcks11_module_path: pkcs11_module_path from the configuration
 */
static int tls_engine_load_dynamic_pkcs11(const char *pkcs11_so_path,
                                          const char *pkcs11_module_path)
{
        char *engine_id = "pkcs11";
        const char *pre_cmd[] = {
                "SO_PATH", NULL /* pkcs11_so_path */,
                "ID", NULL /* engine_id */,
                "LIST_ADD", "1",
                /* "NO_VCHECK", "1", */
                "LOAD", NULL,
                NULL, NULL
        };
        const char *post_cmd[] = {
                "MODULE_PATH", NULL /* pkcs11_module_path */,
                NULL, NULL
        };

        if (!pkcs11_so_path || !pkcs11_module_path)
                return 0;

        pre_cmd[1] = pkcs11_so_path;
        pre_cmd[3] = engine_id;
        post_cmd[1] = pkcs11_module_path;

        wpa_printf(MSG_DEBUG, "ENGINE: Loading pkcs11 Engine from %s",
                   pkcs11_so_path);

        return tls_engine_load_dynamic_generic(pre_cmd, post_cmd, engine_id);
}


/**
 * tls_engine_load_dynamic_opensc - load the opensc engine provided by opensc
 * @opensc_so_path: opensc_so_path from the configuration
 */
static int tls_engine_load_dynamic_opensc(const char *opensc_so_path)
{
        char *engine_id = "opensc";
        const char *pre_cmd[] = {
                "SO_PATH", NULL /* opensc_so_path */,
                "ID", NULL /* engine_id */,
                "LIST_ADD", "1",
                "LOAD", NULL,
                NULL, NULL
        };

        if (!opensc_so_path)
                return 0;

        pre_cmd[1] = opensc_so_path;
        pre_cmd[3] = engine_id;

        wpa_printf(MSG_DEBUG, "ENGINE: Loading OpenSC Engine from %s",
                   opensc_so_path);

        return tls_engine_load_dynamic_generic(pre_cmd, NULL, engine_id);
}
#endif /* OPENSSL_NO_ENGINE */


void * tls_init(const struct tls_config *conf)
{
        SSL_CTX *ssl;

        if (tls_openssl_ref_count == 0) {
                SSL_load_error_strings();
                SSL_library_init();
#ifndef OPENSSL_NO_SHA256
                EVP_add_digest(EVP_sha256());
#endif /* OPENSSL_NO_SHA256 */
                /* TODO: if /dev/urandom is available, PRNG is seeded
                 * automatically. If this is not the case, random data should
                 * be added here. */

#ifdef PKCS12_FUNCS
#ifndef OPENSSL_NO_RC2
                /*
                 * 40-bit RC2 is commonly used in PKCS#12 files, so enable it.
                 * This is enabled by PKCS12_PBE_add() in OpenSSL 0.9.8
                 * versions, but it looks like OpenSSL 1.0.0 does not do that
                 * anymore.
                 */
                EVP_add_cipher(EVP_rc2_40_cbc());
#endif /* OPENSSL_NO_RC2 */
                PKCS12_PBE_add();
#endif  /* PKCS12_FUNCS */
        }
        tls_openssl_ref_count++;

        ssl = SSL_CTX_new(TLSv1_method());
        if (ssl == NULL)
                return NULL;

        SSL_CTX_set_info_callback(ssl, ssl_info_cb);

#ifndef OPENSSL_NO_ENGINE
        if (conf &&
            (conf->opensc_engine_path || conf->pkcs11_engine_path ||
             conf->pkcs11_module_path)) {
                wpa_printf(MSG_DEBUG, "ENGINE: Loading dynamic engine");
                ERR_load_ENGINE_strings();
                ENGINE_load_dynamic();

                if (tls_engine_load_dynamic_opensc(conf->opensc_engine_path) ||
                    tls_engine_load_dynamic_pkcs11(conf->pkcs11_engine_path,
                                                   conf->pkcs11_module_path)) {
                        tls_deinit(ssl);
                        return NULL;
                }
        }
#endif /* OPENSSL_NO_ENGINE */

        return ssl;
}


void tls_deinit(void *ssl_ctx)
{
        SSL_CTX *ssl = ssl_ctx;
        SSL_CTX_free(ssl);

        tls_openssl_ref_count--;
        if (tls_openssl_ref_count == 0) {
#ifndef OPENSSL_NO_ENGINE
                ENGINE_cleanup();
#endif /* OPENSSL_NO_ENGINE */
                CRYPTO_cleanup_all_ex_data();
                ERR_remove_state(0);
                ERR_free_strings();
                EVP_cleanup();
        }
}


static int tls_engine_init(struct tls_connection *conn, const char *engine_id,
                           const char *pin, const char *key_id,
                           const char *cert_id, const char *ca_cert_id)
{
#ifndef OPENSSL_NO_ENGINE
        int ret = -1;
        if (engine_id == NULL) {
                wpa_printf(MSG_ERROR, "ENGINE: Engine ID not set");
                return -1;
        }
        if (pin == NULL) {
                wpa_printf(MSG_ERROR, "ENGINE: Smartcard PIN not set");
                return -1;
        }
        if (key_id == NULL) {
                wpa_printf(MSG_ERROR, "ENGINE: Key Id not set");
                return -1;
        }

        ERR_clear_error();
        conn->engine = ENGINE_by_id(engine_id);
        if (!conn->engine) {
                wpa_printf(MSG_ERROR, "ENGINE: engine %s not available [%s]",
                           engine_id, ERR_error_string(ERR_get_error(), NULL));
                goto err;
        }
        if (ENGINE_init(conn->engine) != 1) {
                wpa_printf(MSG_ERROR, "ENGINE: engine init failed "
                           "(engine: %s) [%s]", engine_id,
                           ERR_error_string(ERR_get_error(), NULL));
                goto err;
        }
        wpa_printf(MSG_DEBUG, "ENGINE: engine initialized");

        if (ENGINE_ctrl_cmd_string(conn->engine, "PIN", pin, 0) == 0) {
                wpa_printf(MSG_ERROR, "ENGINE: cannot set pin [%s]",
                           ERR_error_string(ERR_get_error(), NULL));
                goto err;
        }
        /* load private key first in-case PIN is required for cert */
        conn->private_key = ENGINE_load_private_key(conn->engine,
                                                    key_id, NULL, NULL);
        if (!conn->private_key) {
                wpa_printf(MSG_ERROR, "ENGINE: cannot load private key with id"
                                " '%s' [%s]", key_id,
                           ERR_error_string(ERR_get_error(), NULL));
                ret = TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED;
                goto err;
        }

        /* handle a certificate and/or CA certificate */
        if (cert_id || ca_cert_id) {
                const char *cmd_name = "LOAD_CERT_CTRL";

                /* test if the engine supports a LOAD_CERT_CTRL */
                if (!ENGINE_ctrl(conn->engine, ENGINE_CTRL_GET_CMD_FROM_NAME,
                                 0, (void *)cmd_name, NULL)) {
                        wpa_printf(MSG_ERROR, "ENGINE: engine does not support"
                                   " loading certificates");
                        ret = TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED;
                        goto err;
                }
        }

        return 0;

err:
        if (conn->engine) {
                ENGINE_free(conn->engine);
                conn->engine = NULL;
        }

        if (conn->private_key) {
                EVP_PKEY_free(conn->private_key);
                conn->private_key = NULL;
        }

        return ret;
#else /* OPENSSL_NO_ENGINE */
        return 0;
#endif /* OPENSSL_NO_ENGINE */
}


static void tls_engine_deinit(struct tls_connection *conn)
{
#ifndef OPENSSL_NO_ENGINE
        wpa_printf(MSG_DEBUG, "ENGINE: engine deinit");
        if (conn->private_key) {
                EVP_PKEY_free(conn->private_key);
                conn->private_key = NULL;
        }
        if (conn->engine) {
                ENGINE_finish(conn->engine);
                conn->engine = NULL;
        }
#endif /* OPENSSL_NO_ENGINE */
}


int tls_get_errors(void *ssl_ctx)
{
        int count = 0;
        unsigned long err;

        while ((err = ERR_get_error())) {
                wpa_printf(MSG_INFO, "TLS - SSL error: %s",
                           ERR_error_string(err, NULL));
                count++;
        }

        return count;
}

struct tls_connection * tls_connection_init(void *ssl_ctx)
{
        SSL_CTX *ssl = ssl_ctx;
        struct tls_connection *conn;
        long options;

        conn = os_zalloc(sizeof(*conn));
        if (conn == NULL)
                return NULL;
        conn->ssl = SSL_new(ssl);
        if (conn->ssl == NULL) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to initialize new SSL connection");
                os_free(conn);
                return NULL;
        }

        SSL_set_app_data(conn->ssl, conn);
        options = SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3 |
                SSL_OP_SINGLE_DH_USE;
#ifdef SSL_OP_NO_COMPRESSION
        options |= SSL_OP_NO_COMPRESSION;
#endif /* SSL_OP_NO_COMPRESSION */
        SSL_set_options(conn->ssl, options);

        conn->ssl_in = BIO_new(BIO_s_mem());
        if (!conn->ssl_in) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to create a new BIO for ssl_in");
                SSL_free(conn->ssl);
                os_free(conn);
                return NULL;
        }

        conn->ssl_out = BIO_new(BIO_s_mem());
        if (!conn->ssl_out) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to create a new BIO for ssl_out");
                SSL_free(conn->ssl);
                BIO_free(conn->ssl_in);
                os_free(conn);
                return NULL;
        }

        SSL_set_bio(conn->ssl, conn->ssl_in, conn->ssl_out);

        return conn;
}


void tls_connection_deinit(void *ssl_ctx, struct tls_connection *conn)
{
        if (conn == NULL)
                return;
        SSL_free(conn->ssl);
        tls_engine_deinit(conn);
        os_free(conn->subject_match);
        os_free(conn->altsubject_match);
        os_free(conn->session_ticket);
        os_free(conn);
}


int tls_connection_established(void *ssl_ctx, struct tls_connection *conn)
{
        return conn ? SSL_is_init_finished(conn->ssl) : 0;
}


int tls_connection_shutdown(void *ssl_ctx, struct tls_connection *conn)
{
        if (conn == NULL)
                return -1;

        /* Shutdown previous TLS connection without notifying the peer
         * because the connection was already terminated in practice
         * and "close notify" shutdown alert would confuse AS. */
        SSL_set_quiet_shutdown(conn->ssl, 1);
        SSL_shutdown(conn->ssl);
        return 0;
}


static int tls_match_altsubject_component(X509 *cert, int type,
                                          const char *value, size_t len)
{
        GENERAL_NAME *gen;
        void *ext;
        int i, found = 0;

        ext = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);

        for (i = 0; ext && i < sk_GENERAL_NAME_num(ext); i++) {
                gen = sk_GENERAL_NAME_value(ext, i);
                if (gen->type != type)
                        continue;
                if (os_strlen((char *) gen->d.ia5->data) == len &&
                    os_memcmp(value, gen->d.ia5->data, len) == 0)
                        found++;
        }

        return found;
}


static int tls_match_altsubject(X509 *cert, const char *match)
{
        int type;
        const char *pos, *end;
        size_t len;

        pos = match;
        do {
                if (os_strncmp(pos, "EMAIL:", 6) == 0) {
                        type = GEN_EMAIL;
                        pos += 6;
                } else if (os_strncmp(pos, "DNS:", 4) == 0) {
                        type = GEN_DNS;
                        pos += 4;
                } else if (os_strncmp(pos, "URI:", 4) == 0) {
                        type = GEN_URI;
                        pos += 4;
                } else {
                        wpa_printf(MSG_INFO, "TLS: Invalid altSubjectName "
                                   "match '%s'", pos);
                        return 0;
                }
                end = os_strchr(pos, ';');
                while (end) {
                        if (os_strncmp(end + 1, "EMAIL:", 6) == 0 ||
                            os_strncmp(end + 1, "DNS:", 4) == 0 ||
                            os_strncmp(end + 1, "URI:", 4) == 0)
                                break;
                        end = os_strchr(end + 1, ';');
                }
                if (end)
                        len = end - pos;
                else
                        len = os_strlen(pos);
                if (tls_match_altsubject_component(cert, type, pos, len) > 0)
                        return 1;
                pos = end + 1;
        } while (end);

        return 0;
}


static int tls_verify_cb(int preverify_ok, X509_STORE_CTX *x509_ctx)
{
        char buf[256];
        X509 *err_cert;
        int err, depth;
        SSL *ssl;
        struct tls_connection *conn;
        char *match, *altmatch;

        err_cert = X509_STORE_CTX_get_current_cert(x509_ctx);
        err = X509_STORE_CTX_get_error(x509_ctx);
        depth = X509_STORE_CTX_get_error_depth(x509_ctx);
        ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
                                         SSL_get_ex_data_X509_STORE_CTX_idx());
        X509_NAME_oneline(X509_get_subject_name(err_cert), buf, sizeof(buf));

        conn = SSL_get_app_data(ssl);
        match = conn ? conn->subject_match : NULL;
        altmatch = conn ? conn->altsubject_match : NULL;

        if (!preverify_ok) {
                wpa_printf(MSG_WARNING, "TLS: Certificate verification failed,"
                           " error %d (%s) depth %d for '%s'", err,
                           X509_verify_cert_error_string(err), depth, buf);
        } else {
                wpa_printf(MSG_DEBUG, "TLS: tls_verify_cb - "
                           "preverify_ok=%d err=%d (%s) depth=%d buf='%s'",
                           preverify_ok, err,
                           X509_verify_cert_error_string(err), depth, buf);
                if (depth == 0 && match && os_strstr(buf, match) == NULL) {
                        wpa_printf(MSG_WARNING, "TLS: Subject '%s' did not "
                                   "match with '%s'", buf, match);
                        preverify_ok = 0;
                } else if (depth == 0 && altmatch &&
                           !tls_match_altsubject(err_cert, altmatch)) {
                        wpa_printf(MSG_WARNING, "TLS: altSubjectName match "
                                   "'%s' not found", altmatch);
                        preverify_ok = 0;
                }
        }

        return preverify_ok;
}


#ifndef OPENSSL_NO_STDIO
static int tls_load_ca_der(void *_ssl_ctx, const char *ca_cert)
{
        SSL_CTX *ssl_ctx = _ssl_ctx;
        X509_LOOKUP *lookup;
        int ret = 0;

        lookup = X509_STORE_add_lookup(ssl_ctx->cert_store,
                                       X509_LOOKUP_file());
        if (lookup == NULL) {
                tls_show_errors(MSG_WARNING, __func__,
                                "Failed add lookup for X509 store");
                return -1;
        }

        if (!X509_LOOKUP_load_file(lookup, ca_cert, X509_FILETYPE_ASN1)) {
                unsigned long err = ERR_peek_error();
                tls_show_errors(MSG_WARNING, __func__,
                                "Failed load CA in DER format");
                if (ERR_GET_LIB(err) == ERR_LIB_X509 &&
                    ERR_GET_REASON(err) == X509_R_CERT_ALREADY_IN_HASH_TABLE) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: %s - ignoring "
                                   "cert already in hash table error",
                                   __func__);
                } else
                        ret = -1;
        }

        return ret;
}
#endif /* OPENSSL_NO_STDIO */


static int tls_connection_ca_cert(void *_ssl_ctx, struct tls_connection *conn,
                                  const char *ca_cert, const u8 *ca_cert_blob,
                                  size_t ca_cert_blob_len, const char *ca_path)
{
        SSL_CTX *ssl_ctx = _ssl_ctx;

        /*
         * Remove previously configured trusted CA certificates before adding
         * new ones.
         */
        X509_STORE_free(ssl_ctx->cert_store);
        ssl_ctx->cert_store = X509_STORE_new();
        if (ssl_ctx->cert_store == NULL) {
                wpa_printf(MSG_DEBUG, "OpenSSL: %s - failed to allocate new "
                           "certificate store", __func__);
                return -1;
        }

        if (ca_cert_blob) {
                X509 *cert = d2i_X509(NULL, (OPENSSL_d2i_TYPE) &ca_cert_blob,
                                      ca_cert_blob_len);
                if (cert == NULL) {
                        tls_show_errors(MSG_WARNING, __func__,
                                        "Failed to parse ca_cert_blob");
                        return -1;
                }

                if (!X509_STORE_add_cert(ssl_ctx->cert_store, cert)) {
                        unsigned long err = ERR_peek_error();
                        tls_show_errors(MSG_WARNING, __func__,
                                        "Failed to add ca_cert_blob to "
                                        "certificate store");
                        if (ERR_GET_LIB(err) == ERR_LIB_X509 &&
                            ERR_GET_REASON(err) ==
                            X509_R_CERT_ALREADY_IN_HASH_TABLE) {
                                wpa_printf(MSG_DEBUG, "OpenSSL: %s - ignoring "
                                           "cert already in hash table error",
                                           __func__);
                        } else {
                                X509_free(cert);
                                return -1;
                        }
                }
                X509_free(cert);
                wpa_printf(MSG_DEBUG, "OpenSSL: %s - added ca_cert_blob "
                           "to certificate store", __func__);
                SSL_set_verify(conn->ssl, SSL_VERIFY_PEER, tls_verify_cb);
                return 0;
        }

#ifdef CONFIG_NATIVE_WINDOWS
        if (ca_cert && tls_cryptoapi_ca_cert(ssl_ctx, conn->ssl, ca_cert) ==
            0) {
                wpa_printf(MSG_DEBUG, "OpenSSL: Added CA certificates from "
                           "system certificate store");
                SSL_set_verify(conn->ssl, SSL_VERIFY_PEER, tls_verify_cb);
                return 0;
        }
#endif /* CONFIG_NATIVE_WINDOWS */

        if (ca_cert || ca_path) {
#ifndef OPENSSL_NO_STDIO
                if (SSL_CTX_load_verify_locations(ssl_ctx, ca_cert, ca_path) !=
                    1) {
                        tls_show_errors(MSG_WARNING, __func__,
                                        "Failed to load root certificates");
                        if (ca_cert &&
                            tls_load_ca_der(ssl_ctx, ca_cert) == 0) {
                                wpa_printf(MSG_DEBUG, "OpenSSL: %s - loaded "
                                           "DER format CA certificate",
                                           __func__);
                        } else
                                return -1;
                } else {
                        wpa_printf(MSG_DEBUG, "TLS: Trusted root "
                                   "certificate(s) loaded");
                        tls_get_errors(ssl_ctx);
                }
                SSL_set_verify(conn->ssl, SSL_VERIFY_PEER, tls_verify_cb);
#else /* OPENSSL_NO_STDIO */
                wpa_printf(MSG_DEBUG, "OpenSSL: %s - OPENSSL_NO_STDIO",
                           __func__);
                return -1;
#endif /* OPENSSL_NO_STDIO */
        } else {
                /* No ca_cert configured - do not try to verify server
                 * certificate */
                SSL_set_verify(conn->ssl, SSL_VERIFY_NONE, NULL);
        }

        return 0;
}


static int tls_global_ca_cert(SSL_CTX *ssl_ctx, const char *ca_cert)
{
        if (ca_cert) {
                if (SSL_CTX_load_verify_locations(ssl_ctx, ca_cert, NULL) != 1)
                {
                        tls_show_errors(MSG_WARNING, __func__,
                                        "Failed to load root certificates");
                        return -1;
                }

                wpa_printf(MSG_DEBUG, "TLS: Trusted root "
                           "certificate(s) loaded");

#ifndef OPENSSL_NO_STDIO
                /* Add the same CAs to the client certificate requests */
                SSL_CTX_set_client_CA_list(ssl_ctx,
                                           SSL_load_client_CA_file(ca_cert));
#endif /* OPENSSL_NO_STDIO */
        }

        return 0;
}


int tls_global_set_verify(void *ssl_ctx, int check_crl)
{
        int flags;

        if (check_crl) {
                X509_STORE *cs = SSL_CTX_get_cert_store(ssl_ctx);
                if (cs == NULL) {
                        tls_show_errors(MSG_INFO, __func__, "Failed to get "
                                        "certificate store when enabling "
                                        "check_crl");
                        return -1;
                }
                flags = X509_V_FLAG_CRL_CHECK;
                if (check_crl == 2)
                        flags |= X509_V_FLAG_CRL_CHECK_ALL;
                X509_STORE_set_flags(cs, flags);
        }
        return 0;
}


static int tls_connection_set_subject_match(struct tls_connection *conn,
                                            const char *subject_match,
                                            const char *altsubject_match)
{
        os_free(conn->subject_match);
        conn->subject_match = NULL;
        if (subject_match) {
                conn->subject_match = os_strdup(subject_match);
                if (conn->subject_match == NULL)
                        return -1;
        }

        os_free(conn->altsubject_match);
        conn->altsubject_match = NULL;
        if (altsubject_match) {
                conn->altsubject_match = os_strdup(altsubject_match);
                if (conn->altsubject_match == NULL)
                        return -1;
        }

        return 0;
}


int tls_connection_set_verify(void *ssl_ctx, struct tls_connection *conn,
                              int verify_peer)
{
        static int counter = 0;

        if (conn == NULL)
                return -1;

        if (verify_peer) {
                SSL_set_verify(conn->ssl, SSL_VERIFY_PEER |
                               SSL_VERIFY_FAIL_IF_NO_PEER_CERT |
                               SSL_VERIFY_CLIENT_ONCE, tls_verify_cb);
        } else {
                SSL_set_verify(conn->ssl, SSL_VERIFY_NONE, NULL);
        }

        SSL_set_accept_state(conn->ssl);

        /*
         * Set session id context in order to avoid fatal errors when client
         * tries to resume a session. However, set the context to a unique
         * value in order to effectively disable session resumption for now
         * since not all areas of the server code are ready for it (e.g.,
         * EAP-TTLS needs special handling for Phase 2 after abbreviated TLS
         * handshake).
         */
        counter++;
        SSL_set_session_id_context(conn->ssl,
                                   (const unsigned char *) &counter,
                                   sizeof(counter));

        return 0;
}


static int tls_connection_client_cert(struct tls_connection *conn,
                                      const char *client_cert,
                                      const u8 *client_cert_blob,
                                      size_t client_cert_blob_len)
{
        if (client_cert == NULL && client_cert_blob == NULL)
                return 0;

        if (client_cert_blob &&
            SSL_use_certificate_ASN1(conn->ssl, (u8 *) client_cert_blob,
                                     client_cert_blob_len) == 1) {
                wpa_printf(MSG_DEBUG, "OpenSSL: SSL_use_certificate_ASN1 --> "
                           "OK");
                return 0;
        } else if (client_cert_blob) {
                tls_show_errors(MSG_DEBUG, __func__,
                                "SSL_use_certificate_ASN1 failed");
        }

        if (client_cert == NULL)
                return -1;

#ifndef OPENSSL_NO_STDIO
        if (SSL_use_certificate_file(conn->ssl, client_cert,
                                     SSL_FILETYPE_ASN1) == 1) {
                wpa_printf(MSG_DEBUG, "OpenSSL: SSL_use_certificate_file (DER)"
                           " --> OK");
                return 0;
        } else {
                tls_show_errors(MSG_DEBUG, __func__,
                                "SSL_use_certificate_file (DER) failed");
        }

        if (SSL_use_certificate_file(conn->ssl, client_cert,
                                     SSL_FILETYPE_PEM) == 1) {
                wpa_printf(MSG_DEBUG, "OpenSSL: SSL_use_certificate_file (PEM)"
                           " --> OK");
                return 0;
        } else {
                tls_show_errors(MSG_DEBUG, __func__,
                                "SSL_use_certificate_file (PEM) failed");
        }
#else /* OPENSSL_NO_STDIO */
        wpa_printf(MSG_DEBUG, "OpenSSL: %s - OPENSSL_NO_STDIO", __func__);
#endif /* OPENSSL_NO_STDIO */

        return -1;
}


static int tls_global_client_cert(SSL_CTX *ssl_ctx, const char *client_cert)
{
#ifndef OPENSSL_NO_STDIO
        if (client_cert == NULL)
                return 0;

        if (SSL_CTX_use_certificate_file(ssl_ctx, client_cert,
                                         SSL_FILETYPE_ASN1) != 1 &&
            SSL_CTX_use_certificate_file(ssl_ctx, client_cert,
                                         SSL_FILETYPE_PEM) != 1) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to load client certificate");
                return -1;
        }
        return 0;
#else /* OPENSSL_NO_STDIO */
        if (client_cert == NULL)
                return 0;
        wpa_printf(MSG_DEBUG, "OpenSSL: %s - OPENSSL_NO_STDIO", __func__);
        return -1;
#endif /* OPENSSL_NO_STDIO */
}


static int tls_passwd_cb(char *buf, int size, int rwflag, void *password)
{
        if (password == NULL) {
                return 0;
        }
        os_strlcpy(buf, (char *) password, size);
        return os_strlen(buf);
}


#ifdef PKCS12_FUNCS
static int tls_parse_pkcs12(SSL_CTX *ssl_ctx, SSL *ssl, PKCS12 *p12,
                            const char *passwd)
{
        EVP_PKEY *pkey;
        X509 *cert;
        STACK_OF(X509) *certs;
        int res = 0;
        char buf[256];

        pkey = NULL;
        cert = NULL;
        certs = NULL;
        if (!PKCS12_parse(p12, passwd, &pkey, &cert, &certs)) {
                tls_show_errors(MSG_DEBUG, __func__,
                                "Failed to parse PKCS12 file");
                PKCS12_free(p12);
                return -1;
        }
        wpa_printf(MSG_DEBUG, "TLS: Successfully parsed PKCS12 data");

        if (cert) {
                X509_NAME_oneline(X509_get_subject_name(cert), buf,
                                  sizeof(buf));
                wpa_printf(MSG_DEBUG, "TLS: Got certificate from PKCS12: "
                           "subject='%s'", buf);
                if (ssl) {
                        if (SSL_use_certificate(ssl, cert) != 1)
                                res = -1;
                } else {
                        if (SSL_CTX_use_certificate(ssl_ctx, cert) != 1)
                                res = -1;
                }
                X509_free(cert);
        }

        if (pkey) {
                wpa_printf(MSG_DEBUG, "TLS: Got private key from PKCS12");
                if (ssl) {
                        if (SSL_use_PrivateKey(ssl, pkey) != 1)
                                res = -1;
                } else {
                        if (SSL_CTX_use_PrivateKey(ssl_ctx, pkey) != 1)
                                res = -1;
                }
                EVP_PKEY_free(pkey);
        }

        if (certs) {
                while ((cert = sk_X509_pop(certs)) != NULL) {
                        X509_NAME_oneline(X509_get_subject_name(cert), buf,
                                          sizeof(buf));
                        wpa_printf(MSG_DEBUG, "TLS: additional certificate"
                                   " from PKCS12: subject='%s'", buf);
                        /*
                         * There is no SSL equivalent for the chain cert - so
                         * always add it to the context...
                         */
                        if (SSL_CTX_add_extra_chain_cert(ssl_ctx, cert) != 1) {
                                res = -1;
                                break;
                        }
                }
                sk_X509_free(certs);
        }

        PKCS12_free(p12);

        if (res < 0)
                tls_get_errors(ssl_ctx);

        return res;
}
#endif  /* PKCS12_FUNCS */


static int tls_read_pkcs12(SSL_CTX *ssl_ctx, SSL *ssl, const char *private_key,
                           const char *passwd)
{
#ifdef PKCS12_FUNCS
        FILE *f;
        PKCS12 *p12;

        f = fopen(private_key, "rb");
        if (f == NULL)
                return -1;

        p12 = d2i_PKCS12_fp(f, NULL);
        fclose(f);

        if (p12 == NULL) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to use PKCS#12 file");
                return -1;
        }

        return tls_parse_pkcs12(ssl_ctx, ssl, p12, passwd);

#else /* PKCS12_FUNCS */
        wpa_printf(MSG_INFO, "TLS: PKCS12 support disabled - cannot read "
                   "p12/pfx files");
        return -1;
#endif  /* PKCS12_FUNCS */
}


static int tls_read_pkcs12_blob(SSL_CTX *ssl_ctx, SSL *ssl,
                                const u8 *blob, size_t len, const char *passwd)
{
#ifdef PKCS12_FUNCS
        PKCS12 *p12;

        p12 = d2i_PKCS12(NULL, (OPENSSL_d2i_TYPE) &blob, len);
        if (p12 == NULL) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to use PKCS#12 blob");
                return -1;
        }

        return tls_parse_pkcs12(ssl_ctx, ssl, p12, passwd);

#else /* PKCS12_FUNCS */
        wpa_printf(MSG_INFO, "TLS: PKCS12 support disabled - cannot parse "
                   "p12/pfx blobs");
        return -1;
#endif  /* PKCS12_FUNCS */
}


#ifndef OPENSSL_NO_ENGINE
static int tls_engine_get_cert(struct tls_connection *conn,
                               const char *cert_id,
                               X509 **cert)
{
        /* this runs after the private key is loaded so no PIN is required */
        struct {
                const char *cert_id;
                X509 *cert;
        } params;
        params.cert_id = cert_id;
        params.cert = NULL;

        if (!ENGINE_ctrl_cmd(conn->engine, "LOAD_CERT_CTRL",
                             0, &params, NULL, 1)) {
                wpa_printf(MSG_ERROR, "ENGINE: cannot load client cert with id"
                           " '%s' [%s]", cert_id,
                           ERR_error_string(ERR_get_error(), NULL));
                return TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED;
        }
        if (!params.cert) {
                wpa_printf(MSG_ERROR, "ENGINE: did not properly cert with id"
                           " '%s'", cert_id);
                return TLS_SET_PARAMS_ENGINE_PRV_INIT_FAILED;
        }
        *cert = params.cert;
        return 0;
}
#endif /* OPENSSL_NO_ENGINE */


static int tls_connection_engine_client_cert(struct tls_connection *conn,
                                             const char *cert_id)
{
#ifndef OPENSSL_NO_ENGINE
        X509 *cert;

        if (tls_engine_get_cert(conn, cert_id, &cert))
                return -1;

        if (!SSL_use_certificate(conn->ssl, cert)) {
                tls_show_errors(MSG_ERROR, __func__,
                                "SSL_use_certificate failed");
                X509_free(cert);
                return -1;
        }
        X509_free(cert);
        wpa_printf(MSG_DEBUG, "ENGINE: SSL_use_certificate --> "
                   "OK");
        return 0;

#else /* OPENSSL_NO_ENGINE */
        return -1;
#endif /* OPENSSL_NO_ENGINE */
}


static int tls_connection_engine_ca_cert(void *_ssl_ctx,
                                         struct tls_connection *conn,
                                         const char *ca_cert_id)
{
#ifndef OPENSSL_NO_ENGINE
        X509 *cert;
        SSL_CTX *ssl_ctx = _ssl_ctx;

        if (tls_engine_get_cert(conn, ca_cert_id, &cert))
                return -1;

        /* start off the same as tls_connection_ca_cert */
        X509_STORE_free(ssl_ctx->cert_store);
        ssl_ctx->cert_store = X509_STORE_new();
        if (ssl_ctx->cert_store == NULL) {
                wpa_printf(MSG_DEBUG, "OpenSSL: %s - failed to allocate new "
                           "certificate store", __func__);
                X509_free(cert);
                return -1;
        }
        if (!X509_STORE_add_cert(ssl_ctx->cert_store, cert)) {
                unsigned long err = ERR_peek_error();
                tls_show_errors(MSG_WARNING, __func__,
                                "Failed to add CA certificate from engine "
                                "to certificate store");
                if (ERR_GET_LIB(err) == ERR_LIB_X509 &&
                    ERR_GET_REASON(err) == X509_R_CERT_ALREADY_IN_HASH_TABLE) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: %s - ignoring cert"
                                   " already in hash table error",
                                   __func__);
                } else {
                        X509_free(cert);
                        return -1;
                }
        }
        X509_free(cert);
        wpa_printf(MSG_DEBUG, "OpenSSL: %s - added CA certificate from engine "
                   "to certificate store", __func__);
        SSL_set_verify(conn->ssl, SSL_VERIFY_PEER, tls_verify_cb);
        return 0;

#else /* OPENSSL_NO_ENGINE */
        return -1;
#endif /* OPENSSL_NO_ENGINE */
}


static int tls_connection_engine_private_key(struct tls_connection *conn)
{
#ifndef OPENSSL_NO_ENGINE
        if (SSL_use_PrivateKey(conn->ssl, conn->private_key) != 1) {
                tls_show_errors(MSG_ERROR, __func__,
                                "ENGINE: cannot use private key for TLS");
                return -1;
        }
        if (!SSL_check_private_key(conn->ssl)) {
                tls_show_errors(MSG_INFO, __func__,
                                "Private key failed verification");
                return -1;
        }
        return 0;
#else /* OPENSSL_NO_ENGINE */
        wpa_printf(MSG_ERROR, "SSL: Configuration uses engine, but "
                   "engine support was not compiled in");
        return -1;
#endif /* OPENSSL_NO_ENGINE */
}


static int tls_connection_private_key(void *_ssl_ctx,
                                      struct tls_connection *conn,
                                      const char *private_key,
                                      const char *private_key_passwd,
                                      const u8 *private_key_blob,
                                      size_t private_key_blob_len)
{
        SSL_CTX *ssl_ctx = _ssl_ctx;
        char *passwd;
        int ok;

        if (private_key == NULL && private_key_blob == NULL)
                return 0;

        if (private_key_passwd) {
                passwd = os_strdup(private_key_passwd);
                if (passwd == NULL)
                        return -1;
        } else
                passwd = NULL;

        SSL_CTX_set_default_passwd_cb(ssl_ctx, tls_passwd_cb);
        SSL_CTX_set_default_passwd_cb_userdata(ssl_ctx, passwd);

        ok = 0;
        while (private_key_blob) {
                if (SSL_use_PrivateKey_ASN1(EVP_PKEY_RSA, conn->ssl,
                                            (u8 *) private_key_blob,
                                            private_key_blob_len) == 1) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: SSL_use_PrivateKey_"
                                   "ASN1(EVP_PKEY_RSA) --> OK");
                        ok = 1;
                        break;
                } else {
                        tls_show_errors(MSG_DEBUG, __func__,
                                        "SSL_use_PrivateKey_ASN1(EVP_PKEY_RSA)"
                                        " failed");
                }

                if (SSL_use_PrivateKey_ASN1(EVP_PKEY_DSA, conn->ssl,
                                            (u8 *) private_key_blob,
                                            private_key_blob_len) == 1) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: SSL_use_PrivateKey_"
                                   "ASN1(EVP_PKEY_DSA) --> OK");
                        ok = 1;
                        break;
                } else {
                        tls_show_errors(MSG_DEBUG, __func__,
                                        "SSL_use_PrivateKey_ASN1(EVP_PKEY_DSA)"
                                        " failed");
                }

                if (SSL_use_RSAPrivateKey_ASN1(conn->ssl,
                                               (u8 *) private_key_blob,
                                               private_key_blob_len) == 1) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: "
                                   "SSL_use_RSAPrivateKey_ASN1 --> OK");
                        ok = 1;
                        break;
                } else {
                        tls_show_errors(MSG_DEBUG, __func__,
                                        "SSL_use_RSAPrivateKey_ASN1 failed");
                }

                if (tls_read_pkcs12_blob(ssl_ctx, conn->ssl, private_key_blob,
                                         private_key_blob_len, passwd) == 0) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: PKCS#12 as blob --> "
                                   "OK");
                        ok = 1;
                        break;
                }

                break;
        }

        while (!ok && private_key) {
#ifndef OPENSSL_NO_STDIO
                if (SSL_use_PrivateKey_file(conn->ssl, private_key,
                                            SSL_FILETYPE_ASN1) == 1) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: "
                                   "SSL_use_PrivateKey_File (DER) --> OK");
                        ok = 1;
                        break;
                } else {
                        tls_show_errors(MSG_DEBUG, __func__,
                                        "SSL_use_PrivateKey_File (DER) "
                                        "failed");
                }

                if (SSL_use_PrivateKey_file(conn->ssl, private_key,
                                            SSL_FILETYPE_PEM) == 1) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: "
                                   "SSL_use_PrivateKey_File (PEM) --> OK");
                        ok = 1;
                        break;
                } else {
                        tls_show_errors(MSG_DEBUG, __func__,
                                        "SSL_use_PrivateKey_File (PEM) "
                                        "failed");
                }
#else /* OPENSSL_NO_STDIO */
                wpa_printf(MSG_DEBUG, "OpenSSL: %s - OPENSSL_NO_STDIO",
                           __func__);
#endif /* OPENSSL_NO_STDIO */

                if (tls_read_pkcs12(ssl_ctx, conn->ssl, private_key, passwd)
                    == 0) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: Reading PKCS#12 file "
                                   "--> OK");
                        ok = 1;
                        break;
                }

                if (tls_cryptoapi_cert(conn->ssl, private_key) == 0) {
                        wpa_printf(MSG_DEBUG, "OpenSSL: Using CryptoAPI to "
                                   "access certificate store --> OK");
                        ok = 1;
                        break;
                }

                break;
        }

        if (!ok) {
                wpa_printf(MSG_INFO, "OpenSSL: Failed to load private key");
                os_free(passwd);
                ERR_clear_error();
                return -1;
        }
        ERR_clear_error();
        SSL_CTX_set_default_passwd_cb(ssl_ctx, NULL);
        os_free(passwd);
        
        if (!SSL_check_private_key(conn->ssl)) {
                tls_show_errors(MSG_INFO, __func__, "Private key failed "
                                "verification");
                return -1;
        }

        wpa_printf(MSG_DEBUG, "SSL: Private key loaded successfully");
        return 0;
}


static int tls_global_private_key(SSL_CTX *ssl_ctx, const char *private_key,
                                  const char *private_key_passwd)
{
        char *passwd;

        if (private_key == NULL)
                return 0;

        if (private_key_passwd) {
                passwd = os_strdup(private_key_passwd);
                if (passwd == NULL)
                        return -1;
        } else
                passwd = NULL;

        SSL_CTX_set_default_passwd_cb(ssl_ctx, tls_passwd_cb);
        SSL_CTX_set_default_passwd_cb_userdata(ssl_ctx, passwd);
        if (
#ifndef OPENSSL_NO_STDIO
            SSL_CTX_use_PrivateKey_file(ssl_ctx, private_key,
                                        SSL_FILETYPE_ASN1) != 1 &&
            SSL_CTX_use_PrivateKey_file(ssl_ctx, private_key,
                                        SSL_FILETYPE_PEM) != 1 &&
#endif /* OPENSSL_NO_STDIO */
            tls_read_pkcs12(ssl_ctx, NULL, private_key, passwd)) {
                tls_show_errors(MSG_INFO, __func__,
                                "Failed to load private key");
                os_free(passwd);
                ERR_clear_error();
                return -1;
        }
        os_free(passwd);
        ERR_clear_error();
        SSL_CTX_set_default_passwd_cb(ssl_ctx, NULL);
        
        if (!SSL_CTX_check_private_key(ssl_ctx)) {
                tls_show_errors(MSG_INFO, __func__,
                                "Private key failed verification");
                return -1;
        }

        return 0;
}


static int tls_connection_dh(struct tls_connection *conn, const char *dh_file)
{
#ifdef OPENSSL_NO_DH
        if (dh_file == NULL)
                return 0;
        wpa_printf(MSG_ERROR, "TLS: openssl does not include DH support, but "
                   "dh_file specified");
        return -1;
#else /* OPENSSL_NO_DH */
        DH *dh;
        BIO *bio;

        /* TODO: add support for dh_blob */
        if (dh_file == NULL)
                return 0;
        if (conn == NULL)
                return -1;

        bio = BIO_new_file(dh_file, "r");
        if (bio == NULL) {
                wpa_printf(MSG_INFO, "TLS: Failed to open DH file '%s': %s",
                           dh_file, ERR_error_string(ERR_get_error(), NULL));
                return -1;
        }
        dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
        BIO_free(bio);
#ifndef OPENSSL_NO_DSA
        while (dh == NULL) {
                DSA *dsa;
                wpa_printf(MSG_DEBUG, "TLS: Failed to parse DH file '%s': %s -"
                           " trying to parse as DSA params", dh_file,
                           ERR_error_string(ERR_get_error(), NULL));
                bio = BIO_new_file(dh_file, "r");
                if (bio == NULL)
                        break;
                dsa = PEM_read_bio_DSAparams(bio, NULL, NULL, NULL);
                BIO_free(bio);
                if (!dsa) {
                        wpa_printf(MSG_DEBUG, "TLS: Failed to parse DSA file "
                                   "'%s': %s", dh_file,
                                   ERR_error_string(ERR_get_error(), NULL));
                        break;
                }

                wpa_printf(MSG_DEBUG, "TLS: DH file in DSA param format");
                dh = DSA_dup_DH(dsa);
                DSA_free(dsa);
                if (dh == NULL) {
                        wpa_printf(MSG_INFO, "TLS: Failed to convert DSA "
                                   "params into DH params");
                        break;
                }
                break;
        }
#endif /* !OPENSSL_NO_DSA */
        if (dh == NULL) {
                wpa_printf(MSG_INFO, "TLS: Failed to read/parse DH/DSA file "
                           "'%s'", dh_file);
                return -1;
        }

        if (SSL_set_tmp_dh(conn->ssl, dh) != 1) {
                wpa_printf(MSG_INFO, "TLS: Failed to set DH params from '%s': "
                           "%s", dh_file,
                           ERR_error_string(ERR_get_error(), NULL));
                DH_free(dh);
                return -1;
        }
        DH_free(dh);
        return 0;
#endif /* OPENSSL_NO_DH */
}


static int tls_global_dh(SSL_CTX *ssl_ctx, const char *dh_file)
{
#ifdef OPENSSL_NO_DH
        if (dh_file == NULL)
                return 0;
        wpa_printf(MSG_ERROR, "TLS: openssl does not include DH support, but "
                   "dh_file specified");
        return -1;
#else /* OPENSSL_NO_DH */
        DH *dh;
        BIO *bio;

        /* TODO: add support for dh_blob */
        if (dh_file == NULL)
                return 0;
        if (ssl_ctx == NULL)
                return -1;

        bio = BIO_new_file(dh_file, "r");
        if (bio == NULL) {
                wpa_printf(MSG_INFO, "TLS: Failed to open DH file '%s': %s",
                           dh_file, ERR_error_string(ERR_get_error(), NULL));
                return -1;
        }
        dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
        BIO_free(bio);
#ifndef OPENSSL_NO_DSA
        while (dh == NULL) {
                DSA *dsa;
                wpa_printf(MSG_DEBUG, "TLS: Failed to parse DH file '%s': %s -"
                           " trying to parse as DSA params", dh_file,
                           ERR_error_string(ERR_get_error(), NULL));
                bio = BIO_new_file(dh_file, "r");
                if (bio == NULL)
                        break;
                dsa = PEM_read_bio_DSAparams(bio, NULL, NULL, NULL);
                BIO_free(bio);
                if (!dsa) {
                        wpa_printf(MSG_DEBUG, "TLS: Failed to parse DSA file "
                                   "'%s': %s", dh_file,
                                   ERR_error_string(ERR_get_error(), NULL));
                        break;
                }

                wpa_printf(MSG_DEBUG, "TLS: DH file in DSA param format");
                dh = DSA_dup_DH(dsa);
                DSA_free(dsa);
                if (dh == NULL) {
                        wpa_printf(MSG_INFO, "TLS: Failed to convert DSA "
                                   "params into DH params");
                        break;
                }
                break;
        }
#endif /* !OPENSSL_NO_DSA */
        if (dh == NULL) {
                wpa_printf(MSG_INFO, "TLS: Failed to read/parse DH/DSA file "
                           "'%s'", dh_file);
                return -1;
        }

        if (SSL_CTX_set_tmp_dh(ssl_ctx, dh) != 1) {
                wpa_printf(MSG_INFO, "TLS: Failed to set DH params from '%s': "
                           "%s", dh_file,
                           ERR_error_string(ERR_get_error(), NULL));
                DH_free(dh);
                return -1;
        }
        DH_free(dh);
        return 0;
#endif /* OPENSSL_NO_DH */
}


int tls_connection_get_keys(void *ssl_ctx, struct tls_connection *conn,
                            struct tls_keys *keys)
{
        SSL *ssl;

        if (conn == NULL || keys == NULL)
                return -1;
        ssl = conn->ssl;
        if (ssl == NULL || ssl->s3 == NULL || ssl->session == NULL)
                return -1;

        os_memset(keys, 0, sizeof(*keys));
        keys->master_key = ssl->session->master_key;
        keys->master_key_len = ssl->session->master_key_length;
        keys->client_random = ssl->s3->client_random;
        keys->client_random_len = SSL3_RANDOM_SIZE;
        keys->server_random = ssl->s3->server_random;
        keys->server_random_len = SSL3_RANDOM_SIZE;

        return 0;
}


int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
                       const char *label, int server_random_first,
                       u8 *out, size_t out_len)
{
        return -1;
}


u8 * tls_connection_handshake(void *ssl_ctx, struct tls_connection *conn,
                              const u8 *in_data, size_t in_len,
                              size_t *out_len, u8 **appl_data,
                              size_t *appl_data_len)
{
        int res;
        u8 *out_data;

        if (appl_data)
                *appl_data = NULL;

        /*
         * Give TLS handshake data from the server (if available) to OpenSSL
         * for processing.
         */
        if (in_data &&
            BIO_write(conn->ssl_in, in_data, in_len) < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Handshake failed - BIO_write");
                return NULL;
        }

        /* Initiate TLS handshake or continue the existing handshake */
        res = SSL_connect(conn->ssl);
        if (res != 1) {
                int err = SSL_get_error(conn->ssl, res);
                if (err == SSL_ERROR_WANT_READ)
                        wpa_printf(MSG_DEBUG, "SSL: SSL_connect - want "
                                   "more data");
                else if (err == SSL_ERROR_WANT_WRITE)
                        wpa_printf(MSG_DEBUG, "SSL: SSL_connect - want to "
                                   "write");
                else {
                        tls_show_errors(MSG_INFO, __func__, "SSL_connect");
                        conn->failed++;
                }
        }

        /* Get the TLS handshake data to be sent to the server */
        res = BIO_ctrl_pending(conn->ssl_out);
        wpa_printf(MSG_DEBUG, "SSL: %d bytes pending from ssl_out", res);
        out_data = os_malloc(res == 0 ? 1 : res);
        if (out_data == NULL) {
                wpa_printf(MSG_DEBUG, "SSL: Failed to allocate memory for "
                           "handshake output (%d bytes)", res);
                if (BIO_reset(conn->ssl_out) < 0) {
                        tls_show_errors(MSG_INFO, __func__,
                                        "BIO_reset failed");
                }
                *out_len = 0;
                return NULL;
        }
        res = res == 0 ? 0 : BIO_read(conn->ssl_out, out_data, res);
        if (res < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Handshake failed - BIO_read");
                if (BIO_reset(conn->ssl_out) < 0) {
                        tls_show_errors(MSG_INFO, __func__,
                                        "BIO_reset failed");
                }
                *out_len = 0;
                return NULL;
        }
        *out_len = res;

        if (SSL_is_init_finished(conn->ssl) && appl_data) {
                *appl_data = os_malloc(in_len);
                if (*appl_data) {
                        res = SSL_read(conn->ssl, *appl_data, in_len);
                        if (res < 0) {
                                int err = SSL_get_error(conn->ssl, res);
                                if (err == SSL_ERROR_WANT_READ ||
                                    err == SSL_ERROR_WANT_WRITE) {
                                        wpa_printf(MSG_DEBUG,
                                                   "SSL: No Application Data "
                                                   "included");
                                } else {
                                        tls_show_errors(MSG_INFO, __func__,
                                                        "Failed to read "
                                                        "possible "
                                                        "Application Data");
                                }
                                os_free(*appl_data);
                                *appl_data = NULL;
                        } else {
                                *appl_data_len = res;
                                wpa_hexdump_key(MSG_MSGDUMP, "SSL: Application"
                                                " Data in Finish message",
                                                *appl_data, *appl_data_len);
                        }
                }
        }

        return out_data;
}


u8 * tls_connection_server_handshake(void *ssl_ctx,
                                     struct tls_connection *conn,
                                     const u8 *in_data, size_t in_len,
                                     size_t *out_len)
{
        int res;
        u8 *out_data;

        /*
         * Give TLS handshake data from the client (if available) to OpenSSL
         * for processing.
         */
        if (in_data &&
            BIO_write(conn->ssl_in, in_data, in_len) < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Handshake failed - BIO_write");
                return NULL;
        }

        /* Initiate TLS handshake or continue the existing handshake */
        res = SSL_accept(conn->ssl);
        if (res != 1) {
                int err = SSL_get_error(conn->ssl, res);
                if (err == SSL_ERROR_WANT_READ)
                        wpa_printf(MSG_DEBUG, "SSL: SSL_accept - want "
                                   "more data");
                else if (err == SSL_ERROR_WANT_WRITE)
                        wpa_printf(MSG_DEBUG, "SSL: SSL_accept - want to "
                                   "write");
                else {
                        tls_show_errors(MSG_INFO, __func__, "SSL_accept");
                        return NULL;
                }
        }

        /* Get the TLS handshake data to be sent to the client */
        res = BIO_ctrl_pending(conn->ssl_out);
        wpa_printf(MSG_DEBUG, "SSL: %d bytes pending from ssl_out", res);
        out_data = os_malloc(res == 0 ? 1 : res);
        if (out_data == NULL) {
                wpa_printf(MSG_DEBUG, "SSL: Failed to allocate memory for "
                           "handshake output (%d bytes)", res);
                if (BIO_reset(conn->ssl_out) < 0) {
                        tls_show_errors(MSG_INFO, __func__,
                                        "BIO_reset failed");
                }
                *out_len = 0;
                return NULL;
        }
        res = res == 0 ? 0 : BIO_read(conn->ssl_out, out_data, res);
        if (res < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Handshake failed - BIO_read");
                if (BIO_reset(conn->ssl_out) < 0) {
                        tls_show_errors(MSG_INFO, __func__,
                                        "BIO_reset failed");
                }
                *out_len = 0;
                return NULL;
        }
        *out_len = res;
        return out_data;
}


int tls_connection_encrypt(void *ssl_ctx, struct tls_connection *conn,
                           const u8 *in_data, size_t in_len,
                           u8 *out_data, size_t out_len)
{
        int res;

        if (conn == NULL)
                return -1;

        /* Give plaintext data for OpenSSL to encrypt into the TLS tunnel. */
        if ((res = BIO_reset(conn->ssl_in)) < 0 ||
            (res = BIO_reset(conn->ssl_out)) < 0) {
                tls_show_errors(MSG_INFO, __func__, "BIO_reset failed");
                return res;
        }
        res = SSL_write(conn->ssl, in_data, in_len);
        if (res < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Encryption failed - SSL_write");
                return res;
        }

        /* Read encrypted data to be sent to the server */
        res = BIO_read(conn->ssl_out, out_data, out_len);
        if (res < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Encryption failed - BIO_read");
                return res;
        }

        return res;
}


int tls_connection_decrypt(void *ssl_ctx, struct tls_connection *conn,
                           const u8 *in_data, size_t in_len,
                           u8 *out_data, size_t out_len)
{
        int res;

        /* Give encrypted data from TLS tunnel for OpenSSL to decrypt. */
        res = BIO_write(conn->ssl_in, in_data, in_len);
        if (res < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Decryption failed - BIO_write");
                return res;
        }
        if (BIO_reset(conn->ssl_out) < 0) {
                tls_show_errors(MSG_INFO, __func__, "BIO_reset failed");
                return res;
        }

        /* Read decrypted data for further processing */
        res = SSL_read(conn->ssl, out_data, out_len);
        if (res < 0) {
                tls_show_errors(MSG_INFO, __func__,
                                "Decryption failed - SSL_read");
                return res;
        }

        return res;
}


int tls_connection_resumed(void *ssl_ctx, struct tls_connection *conn)
{
        return conn ? conn->ssl->hit : 0;
}


int tls_connection_set_cipher_list(void *tls_ctx, struct tls_connection *conn,
                                   u8 *ciphers)
{
        char buf[100], *pos, *end;
        u8 *c;
        int ret;

        if (conn == NULL || conn->ssl == NULL || ciphers == NULL)
                return -1;

        buf[0] = '\0';
        pos = buf;
        end = pos + sizeof(buf);

        c = ciphers;
        while (*c != TLS_CIPHER_NONE) {
                const char *suite;

                switch (*c) {
                case TLS_CIPHER_RC4_SHA:
                        suite = "RC4-SHA";
                        break;
                case TLS_CIPHER_AES128_SHA:
                        suite = "AES128-SHA";
                        break;
                case TLS_CIPHER_RSA_DHE_AES128_SHA:
                        suite = "DHE-RSA-AES128-SHA";
                        break;
                case TLS_CIPHER_ANON_DH_AES128_SHA:
                        suite = "ADH-AES128-SHA";
                        break;
                default:
                        wpa_printf(MSG_DEBUG, "TLS: Unsupported "
                                   "cipher selection: %d", *c);
                        return -1;
                }
                ret = os_snprintf(pos, end - pos, ":%s", suite);
                if (ret < 0 || ret >= end - pos)
                        break;
                pos += ret;

                c++;
        }

        wpa_printf(MSG_DEBUG, "OpenSSL: cipher suites: %s", buf + 1);

        if (SSL_set_cipher_list(conn->ssl, buf + 1) != 1) {
                tls_show_errors(MSG_INFO, __func__,
                                "Cipher suite configuration failed");
                return -1;
        }

        return 0;
}


int tls_get_cipher(void *ssl_ctx, struct tls_connection *conn,
                   char *buf, size_t buflen)
{
        const char *name;
        if (conn == NULL || conn->ssl == NULL)
                return -1;

        name = SSL_get_cipher(conn->ssl);
        if (name == NULL)
                return -1;

        os_strlcpy(buf, name, buflen);
        return 0;
}


int tls_connection_enable_workaround(void *ssl_ctx,
                                     struct tls_connection *conn)
{
        SSL_set_options(conn->ssl, SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS);

        return 0;
}


#if defined(EAP_FAST) || defined(EAP_FAST_DYNAMIC)
/* ClientHello TLS extensions require a patch to openssl, so this function is
 * commented out unless explicitly needed for EAP-FAST in order to be able to
 * build this file with unmodified openssl. */
int tls_connection_client_hello_ext(void *ssl_ctx, struct tls_connection *conn,
                                    int ext_type, const u8 *data,
                                    size_t data_len)
{
        if (conn == NULL || conn->ssl == NULL || ext_type != 35)
                return -1;

#ifdef CONFIG_OPENSSL_TICKET_OVERRIDE
        if (SSL_set_session_ticket_ext(conn->ssl, (void *) data,
                                       data_len) != 1)
                return -1;
#else /* CONFIG_OPENSSL_TICKET_OVERRIDE */
        if (SSL_set_hello_extension(conn->ssl, ext_type, (void *) data,
                                    data_len) != 1)
                return -1;
#endif /* CONFIG_OPENSSL_TICKET_OVERRIDE */

        return 0;
}
#endif /* EAP_FAST || EAP_FAST_DYNAMIC */


int tls_connection_get_failed(void *ssl_ctx, struct tls_connection *conn)
{
        if (conn == NULL)
                return -1;
        return conn->failed;
}


int tls_connection_get_read_alerts(void *ssl_ctx, struct tls_connection *conn)
{
        if (conn == NULL)
                return -1;
        return conn->read_alerts;
}


int tls_connection_get_write_alerts(void *ssl_ctx, struct tls_connection *conn)
{
        if (conn == NULL)
                return -1;
        return conn->write_alerts;
}


int tls_connection_set_params(void *tls_ctx, struct tls_connection *conn,
                              const struct tls_connection_params *params)
{
        int ret;
        unsigned long err;

        if (conn == NULL)
                return -1;

        while ((err = ERR_get_error())) {
                wpa_printf(MSG_INFO, "%s: Clearing pending SSL error: %s",
                           __func__, ERR_error_string(err, NULL));
        }

        if (params->engine) {
                wpa_printf(MSG_DEBUG, "SSL: Initializing TLS engine");
                ret = tls_engine_init(conn, params->engine_id, params->pin,
                                      params->key_id, params->cert_id,
                                      params->ca_cert_id);
                if (ret)
                        return ret;
        }
        if (tls_connection_set_subject_match(conn,
                                             params->subject_match,
                                             params->altsubject_match))
                return -1;

        if (params->engine && params->ca_cert_id) {
                if (tls_connection_engine_ca_cert(tls_ctx, conn,
                                                  params->ca_cert_id))
                        return TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED;
        } else if (tls_connection_ca_cert(tls_ctx, conn, params->ca_cert,
                                          params->ca_cert_blob,
                                          params->ca_cert_blob_len,
                                          params->ca_path))
                return -1;

        if (params->engine && params->cert_id) {
                if (tls_connection_engine_client_cert(conn, params->cert_id))
                        return TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED;
        } else if (tls_connection_client_cert(conn, params->client_cert,
                                              params->client_cert_blob,
                                              params->client_cert_blob_len))
                return -1;

        if (params->engine && params->key_id) {
                wpa_printf(MSG_DEBUG, "TLS: Using private key from engine");
                if (tls_connection_engine_private_key(conn))
                        return TLS_SET_PARAMS_ENGINE_PRV_VERIFY_FAILED;
        } else if (tls_connection_private_key(tls_ctx, conn,
                                              params->private_key,
                                              params->private_key_passwd,
                                              params->private_key_blob,
                                              params->private_key_blob_len)) {
                wpa_printf(MSG_INFO, "TLS: Failed to load private key '%s'",
                           params->private_key);
                return -1;
        }

        if (tls_connection_dh(conn, params->dh_file)) {
                wpa_printf(MSG_INFO, "TLS: Failed to load DH file '%s'",
                           params->dh_file);
                return -1;
        }

        tls_get_errors(tls_ctx);

        return 0;
}


int tls_global_set_params(void *tls_ctx,
                          const struct tls_connection_params *params)
{
        SSL_CTX *ssl_ctx = tls_ctx;
        unsigned long err;

        while ((err = ERR_get_error())) {
                wpa_printf(MSG_INFO, "%s: Clearing pending SSL error: %s",
                           __func__, ERR_error_string(err, NULL));
        }

        if (tls_global_ca_cert(ssl_ctx, params->ca_cert))
                return -1;

        if (tls_global_client_cert(ssl_ctx, params->client_cert))
                return -1;

        if (tls_global_private_key(ssl_ctx, params->private_key,
                                   params->private_key_passwd))
                return -1;

        if (tls_global_dh(ssl_ctx, params->dh_file)) {
                wpa_printf(MSG_INFO, "TLS: Failed to load DH file '%s'",
                           params->dh_file);
                return -1;
        }

        return 0;
}


int tls_connection_get_keyblock_size(void *tls_ctx,
                                     struct tls_connection *conn)
{
        const EVP_CIPHER *c;
        const EVP_MD *h;

        if (conn == NULL || conn->ssl == NULL ||
            conn->ssl->enc_read_ctx == NULL ||
            conn->ssl->enc_read_ctx->cipher == NULL ||
            conn->ssl->read_hash == NULL)
                return -1;

        c = conn->ssl->enc_read_ctx->cipher;
#if OPENSSL_VERSION_NUMBER >= 0x00909000L
        h = EVP_MD_CTX_md(conn->ssl->read_hash);
#else
        h = conn->ssl->read_hash;
#endif

        return 2 * (EVP_CIPHER_key_length(c) +
                    EVP_MD_size(h) +
                    EVP_CIPHER_iv_length(c));
}


unsigned int tls_capabilities(void *tls_ctx)
{
        return 0;
}


int tls_connection_set_ia(void *tls_ctx, struct tls_connection *conn,
                          int tls_ia)
{
        return -1;
}


int tls_connection_ia_send_phase_finished(void *tls_ctx,
                                          struct tls_connection *conn,
                                          int final,
                                          u8 *out_data, size_t out_len)
{
        return -1;
}


int tls_connection_ia_final_phase_finished(void *tls_ctx,
                                           struct tls_connection *conn)
{
        return -1;
}


int tls_connection_ia_permute_inner_secret(void *tls_ctx,
                                           struct tls_connection *conn,
                                           const u8 *key, size_t key_len)
{
        return -1;
}


#if defined(EAP_FAST) || defined(EAP_FAST_DYNAMIC)
/* Pre-shared secred requires a patch to openssl, so this function is
 * commented out unless explicitly needed for EAP-FAST in order to be able to
 * build this file with unmodified openssl. */

static int tls_sess_sec_cb(SSL *s, void *secret, int *secret_len,
                           STACK_OF(SSL_CIPHER) *peer_ciphers,
                           SSL_CIPHER **cipher, void *arg)
{
        struct tls_connection *conn = arg;
        int ret;

        if (conn == NULL || conn->session_ticket_cb == NULL)
                return 0;

        ret = conn->session_ticket_cb(conn->session_ticket_cb_ctx,
                                      conn->session_ticket,
                                      conn->session_ticket_len,
                                      s->s3->client_random,
                                      s->s3->server_random, secret);
        os_free(conn->session_ticket);
        conn->session_ticket = NULL;

        if (ret <= 0)
                return 0;

        *secret_len = SSL_MAX_MASTER_KEY_LENGTH;
        return 1;
}


#ifdef CONFIG_OPENSSL_TICKET_OVERRIDE
static int tls_session_ticket_ext_cb(SSL *s, const unsigned char *data,
                                     int len, void *arg)
{
        struct tls_connection *conn = arg;

        if (conn == NULL || conn->session_ticket_cb == NULL)
                return 0;

        wpa_printf(MSG_DEBUG, "OpenSSL: %s: length=%d", __func__, len);

        os_free(conn->session_ticket);
        conn->session_ticket = NULL;

        wpa_hexdump(MSG_DEBUG, "OpenSSL: ClientHello SessionTicket "
                    "extension", data, len);

        conn->session_ticket = os_malloc(len);
        if (conn->session_ticket == NULL)
                return 0;

        os_memcpy(conn->session_ticket, data, len);
        conn->session_ticket_len = len;

        return 1;
}
#else /* CONFIG_OPENSSL_TICKET_OVERRIDE */
#ifdef SSL_OP_NO_TICKET
static void tls_hello_ext_cb(SSL *s, int client_server, int type,
                             unsigned char *data, int len, void *arg)
{
        struct tls_connection *conn = arg;

        if (conn == NULL || conn->session_ticket_cb == NULL)
                return;

        wpa_printf(MSG_DEBUG, "OpenSSL: %s: type=%d length=%d", __func__,
                   type, len);

        if (type == TLSEXT_TYPE_session_ticket && !client_server) {
                os_free(conn->session_ticket);
                conn->session_ticket = NULL;

                wpa_hexdump(MSG_DEBUG, "OpenSSL: ClientHello SessionTicket "
                            "extension", data, len);
                conn->session_ticket = os_malloc(len);
                if (conn->session_ticket == NULL)
                        return;

                os_memcpy(conn->session_ticket, data, len);
                conn->session_ticket_len = len;
        }
}
#else /* SSL_OP_NO_TICKET */
static int tls_hello_ext_cb(SSL *s, TLS_EXTENSION *ext, void *arg)
{
        struct tls_connection *conn = arg;

        if (conn == NULL || conn->session_ticket_cb == NULL)
                return 0;

        wpa_printf(MSG_DEBUG, "OpenSSL: %s: type=%d length=%d", __func__,
                   ext->type, ext->length);

        os_free(conn->session_ticket);
        conn->session_ticket = NULL;

        if (ext->type == 35) {
                wpa_hexdump(MSG_DEBUG, "OpenSSL: ClientHello SessionTicket "
                            "extension", ext->data, ext->length);
                conn->session_ticket = os_malloc(ext->length);
                if (conn->session_ticket == NULL)
                        return SSL_AD_INTERNAL_ERROR;

                os_memcpy(conn->session_ticket, ext->data, ext->length);
                conn->session_ticket_len = ext->length;
        }

        return 0;
}
#endif /* SSL_OP_NO_TICKET */
#endif /* CONFIG_OPENSSL_TICKET_OVERRIDE */
#endif /* EAP_FAST || EAP_FAST_DYNAMIC */


int tls_connection_set_session_ticket_cb(void *tls_ctx,
                                         struct tls_connection *conn,
                                         tls_session_ticket_cb cb,
                                         void *ctx)
{
#if defined(EAP_FAST) || defined(EAP_FAST_DYNAMIC)
        conn->session_ticket_cb = cb;
        conn->session_ticket_cb_ctx = ctx;

        if (cb) {
                if (SSL_set_session_secret_cb(conn->ssl, tls_sess_sec_cb,
                                              conn) != 1)
                        return -1;
#ifdef CONFIG_OPENSSL_TICKET_OVERRIDE
                SSL_set_session_ticket_ext_cb(conn->ssl,
                                              tls_session_ticket_ext_cb, conn);
#else /* CONFIG_OPENSSL_TICKET_OVERRIDE */
#ifdef SSL_OP_NO_TICKET
                SSL_set_tlsext_debug_callback(conn->ssl, tls_hello_ext_cb);
                SSL_set_tlsext_debug_arg(conn->ssl, conn);
#else /* SSL_OP_NO_TICKET */
                if (SSL_set_hello_extension_cb(conn->ssl, tls_hello_ext_cb,
                                               conn) != 1)
                        return -1;
#endif /* SSL_OP_NO_TICKET */
#endif /* CONFIG_OPENSSL_TICKET_OVERRIDE */
        } else {
                if (SSL_set_session_secret_cb(conn->ssl, NULL, NULL) != 1)
                        return -1;
#ifdef CONFIG_OPENSSL_TICKET_OVERRIDE
                SSL_set_session_ticket_ext_cb(conn->ssl, NULL, NULL);
#else /* CONFIG_OPENSSL_TICKET_OVERRIDE */
#ifdef SSL_OP_NO_TICKET
                SSL_set_tlsext_debug_callback(conn->ssl, NULL);
                SSL_set_tlsext_debug_arg(conn->ssl, conn);
#else /* SSL_OP_NO_TICKET */
                if (SSL_set_hello_extension_cb(conn->ssl, NULL, NULL) != 1)
                        return -1;
#endif /* SSL_OP_NO_TICKET */
#endif /* CONFIG_OPENSSL_TICKET_OVERRIDE */
        }

        return 0;
#else /* EAP_FAST || EAP_FAST_DYNAMIC */
        return -1;
#endif /* EAP_FAST || EAP_FAST_DYNAMIC */
}
